Recently, the Internet has rapidly become popular even at home with electronic commerce being carried on over the Internet. For example, SET (Secure Electronic Transaction) is known as a protocol for making a card account settlement over the Internet. A card member (cardholder) installs a SET-dedicated application, called Wallet, into his or her own personal computer (PC), while a merchant that opens a virtual store installs a SET-dedicated application into the web server. The user browses the web pages of the sites of virtual stores with a browser, which is provided for browsing the World-Wide Web (WWW), to select a product the user wants to purchase. This purchase instruction starts the Wallet on the personal computer to make a card account settlement with the settlement gateway (payment gateway). After that, the product is sent from the merchant to the user.
For the details on the SET, see “USING SET for Secure Electronic Commerce” written by Grady N. Drew and translated by Takeaki Ota, Pearson Education Co.
On the other hand, while a personal computer has been used conventionally as a primary tool for accessing the Internet, a non-PC apparatus, such as a cellular phone (including a PHS: Personal Handy phone System), television set, video game machine, word processor, and car navigator are used now for this purpose (For sake of convenience, those information terminals are called information home electric appliances in this specification). Therefore, it is desired that electronic commerce be carried on easily and securely even on those information home electric appliances.
However, because user's ability to directly access data (files) stored in an internal storage device (for example, a hard disk device) of a standard personal computer requires some special measures and, because a special security protocol is used, a SET-dedicated application must be large in size. For this reason, on an information home electric appliance, especially a cellular phone on which a large-capacity memory device cannot be included, there is a limit on the size of an installable application (program) and therefore it is difficult to install the application described above.
In view of the foregoing, it is an object of the present invention to allow even an information home electric appliance with only a relatively small capacity storage device to conduct relatively secure transactions on the Internet with a credit card.